1. Field of the Invention
This invention relates to an arming unit retention mechanism and methods of use thereof. The invention hybridizes conventional arming unit technology with zero retention force arming unit technology to provide an arming unit which releases armed weapons with zero retention force and which releases unarmed weapons even in the event of a release system failure.
2. Description of the Related Art
Arming unit retention mechanisms are used in conjunction with bomb racks, aircraft pylon, or other weapons release systems that use weapons which are armed by the pulling of a lanyard. In these arming unit systems, a hook retains the weapon lanyard such that when the weapon is released, the lanyard is pulled, and the weapon is armed by the pulling of the lanyard. Additionally, at times it is desired to release an unarmed weapon. These arming unit systems permit the plunger or hook to be disengaged from the weapon lanyard such that when the weapon is released, the lanyard is not pulled, and the weapon is released unarmed. Exemplary weapons release systems that use such arming units include the BRU-36 bomb rack, used on the AV-8 aircraft, and the BRU-32/33 bomb racks used on the F-18 aircraft.
Two types of arming unit (hereinafter xe2x80x9cAUxe2x80x9d) retention mechanisms are commonly known in the art, conventional AU technology and zero retention force (hereinafter xe2x80x9cZRFxe2x80x9d) AU technology.
As described above, at times it is desired to release an unarmed weapon. In conventional AU mechanisms, in order to release an unarmed weapon the user must provide the force necessary (typically 10-12 pounds of force) to disengage the hook from the lanyard. If the user is unable to provide this force, or if the mechanism fails for whatever reason, the AU does not open and an armed weapon is released instead of the desired unarmed weapon.
In ZRF AU mechanisms, the lanyard is disengaged by the driving of a mechanical linkage for opening the lanyard hook. If this mechanism fails for whatever reason, the ZRF AU does not open and an armed weapon is released instead of the desired unarmed weapon.
Neither the conventional AU or the ZRF AU allows zero retention and a fail safe mode of release if the mechanism fails. Furthermore, in the event of inadvertent weapon release resulting from mechanical failure of the bomb rack, the current arming units would retain the lanyard and release an armed weapon. Therefore, there is a continuing need for a zero retention release of unarmed weapons that provides a fail safe in the event of mechanism failure.
Additionally, the current equipment in the field is equipped with either one of the two above mentioned systems. Accordingly, there is a continuing need for a zero retention force release of unarmed weapons that provides a fail safe in the event of mechanism failure, and which can be retrofitted to the existing equipment.
The apparatus and method of the present invention relies on a mechanical force acting on a lanyard hook to provide zero retention force disengagement of the lanyard from the hook when the apparatus is in an Open mode. However, in the event this system fails, the lanyard hook of the present invention still releases the lanyard by using the weight of the weapon as the force to open the hook when the apparatus is in either the Open or Normal modes. The lanyard hook of the apparatus locks closed only when the apparatus is in a Locked mode.